First movie to feature cuckold?
Peckinpah always at the forefront
shareActually, there was a movie from 1966 called Cul-de-sac, directed by Roman Polanski and starring Donald Pleasance and Lionel Stander ("Max" from TV's Hart to Hart) that featured Pleasance as a retired professor/writer who was being cheated on by his much-younger wife.
When they are alone, they play games where she dresses him up in women's make-up and a nightie, and when they hear a burglar, Pleasance cautiously approaches the burglar with a frying pan....in drag.
But I agree with your point — cuckolded men are usually minor roles, not leading men or supporting roles.